i did a compression test today,

1-225
2-225
3-220
4-217

is that good

07 ss/sc 52k on it.

looked in to see the pistons and did see a little oil on pistons is the normal.
car runs great, just did it cuss i was bored and needed to chang the plugs so fig i would do it and see the results.

 

bump
still need to clean the filter and MAF, the TB is spotless as is the CAI. going to put on new fuel filter tomorrow

 

Thats pretty damn high, mine was 155,160,160,160 on a cold/dry check.

 

mine was worm dry crank as the car sat for a hour or so. i thought something was wrong, so i called gm serves and they said that's really good like new. worm test is how they would do it too. he said that's cuss it take time to get everything ready for the test. oh and that was with WOT. he said that i should do a leak down test to make sure the valve seats are good as well. and that the little bit of oil that i see on the pistons is normal.

 

I think as long as all 4 cylinders have similar compression you are fine.

 

so no need for a leak down test

 

i would still do the leak down test just to check everything

but yeah those numbers are really good

 

^this, but your compression numbers shouldnt worry you.

 

as long as they are over 100 and within 10% of eachother you are fine.

My LNF did 125 130 130 125. but im at 5500 ft altitude.

 

that's peachy but you should still do a leak down an engine can past a comp test but fail a leak down test

an engine can pass a comp test but fail a leak down

yours needs some help

wrong

 

there really aint no help other then replacing the pistons, i know u had something about replacing the rings but id have to hone the sleeves to do that and by the time I do all that I may as well buy new pistons, and if I buy new pistons I may as well sleeve the block and you get my point lol.

 

I do if you decide to do pistons I got a set of .010 10to1 slugs laying around id make someone a great deal on

 

wouldnt his numbers be higher if he did it when it was at operating temp?

 

Alot of different thoughts in here....

GM spec is over 100psi and within 10% of the average. This spec is used on everything I have seen and it is just a guideline.

Some people have different numbers for many reasons. Mostly gauge difference's. They are just like dyno's but even worse because no one ever gets a compression gauge calibrated.

Engine temp does affect readings, so does engine wear.

As long as your numbers are all close to each other you should be fine, if you feel they are low try a different gauge before tearing the engine apart.

 

good points, but to check the OVERALL health of an engine you should do a compression AND leak down test.

 

Ever taken an ASE test? This sounds like a question on one of them lol.

I only do these tests when something isn't right. Normally this is found right away by a compression test. But if you feel like doing a bunch of tests on a good engine, you might as well do a running compression test and I would also use a manometer to measure crankcase pressure and then back pressure in the exhaust.

My point is don't do more work than you have to, unless you are bored and just want to.

 

I would agree to a point but I have seen plenty of engines pass a comp test and fail a leakdown test

 

The resin I did the compression test was because I was bored and was changing the plugs anyway, so thought sense it's apart I might as well test it. I do drive my car purity hard, Not all the time. I like to do Burnouts occasionally, and take it to the red line at WOT in 2-3 gear. I hit the rev limiter wants in awhile, but not on purpose.

"manometer to measure crankcase pressure and then back pressure in the exhaust" is that easy to do, and does it take specialized tool. oh hell, I will Google "manometer" and how to.,,,

Thanks, Josh

 

i have taken a couple small tests online. i want to become ASE certified eventually though.

now you are just showing off with all of these fancy words and tests!!

 

you know what a.s.e means ASK SOMEONE ELSE

 

I think what he's getting at is that if a car passes the comp test *and* is running like a champ, no reason to waste time doing a leakdown test as well. Of course if something was off and the comp test still passed, leakdown is certainly something worth doing to help diagnose a problem.

 

The car runs better than when it was new, there is nothing wrong with the engine at all. I just wanted to see what the compression was at. I not going to do the Leak down test.

I always change my oil when it's at 50% oil life. and use Royal Purple HPS 5-w30, and ZMAX oil treatment, And ZMAX fuel treatment, at every oil change,

The clutch slips a little wants in awhile, but only under hard pull, it's not really that noticeable. but the throw-out bearing is making a rattling noise when i let the clutch out. I can only hear it at idle. It sound like ****. I ordered a new "LSJ Trans with LSD", and a Clutchmasters stage 2 with trow-out bearing. it's just sitting in my shed till I have the time to drop it in.

So after I install the New Trans, the car should be performing at IT'S peak performance.

 

wait you ordered a full trans! wanted the LSD that bad eh?

 

Yep I did. I am not going to tear my trans apart, for the price it would cost to do that. Just spend couple hundred more for new one, then just install it myself. BAM'.... new trans with LSD. and a stage 2 clutch with bearing.